percpu: refactor percpu.h

Impact: cleanup

Refactor the DEFINE_PER_CPU_* macros and add .data.percpu.first
section.

Signed-off-by: Brian Gerst <brgerst@gmail.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

2 files changed, 24 insertions, 18 deletions

diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm-generic/vmlinux.lds.h
index aa6b9b1b30b5..32bbf50d3055 100644
--- a/include/asm-generic/vmlinux.lds.h
+++ b/include/asm-generic/vmlinux.lds.h
@@ -486,6 +486,7 @@
  */
 #define PERCPU_VADDR(vaddr, phdr)                                       \
         PERCPU_PROLOG(vaddr)                                            \
+                *(.data.percpu.first)                                   \
                 *(.data.percpu.page_aligned)                            \
                 *(.data.percpu)                                         \
                 *(.data.percpu.shared_aligned)                          \
diff --git a/include/linux/percpu.h b/include/linux/percpu.h
index 9f2a3751873a..0e24202b5a4e 100644
--- a/include/linux/percpu.h
+++ b/include/linux/percpu.h
@@ -9,34 +9,39 @@
 #include <asm/percpu.h>
 
 #ifdef CONFIG_SMP
-#define DEFINE_PER_CPU(type, name)                                      \
-        __attribute__((__section__(".data.percpu")))                    \
-        PER_CPU_ATTRIBUTES __typeof__(type) per_cpu__##name
+#define PER_CPU_BASE_SECTION ".data.percpu"
 
 #ifdef MODULE
-#define SHARED_ALIGNED_SECTION ".data.percpu"
+#define PER_CPU_SHARED_ALIGNED_SECTION ""
 #else
-#define SHARED_ALIGNED_SECTION ".data.percpu.shared_aligned"
+#define PER_CPU_SHARED_ALIGNED_SECTION ".shared_aligned"
 #endif
+#define PER_CPU_FIRST_SECTION ".first"
 
-#define DEFINE_PER_CPU_SHARED_ALIGNED(type, name)                       \
-        __attribute__((__section__(SHARED_ALIGNED_SECTION)))            \
-        PER_CPU_ATTRIBUTES __typeof__(type) per_cpu__##name             \
-        ____cacheline_aligned_in_smp
+#else
+
+#define PER_CPU_BASE_SECTION ".data"
+#define PER_CPU_SHARED_ALIGNED_SECTION ""
+#define PER_CPU_FIRST_SECTION ""
+
+#endif
 
-#define DEFINE_PER_CPU_PAGE_ALIGNED(type, name)                 \
-        __attribute__((__section__(".data.percpu.page_aligned")))       \
+#define DEFINE_PER_CPU_SECTION(type, name, section)                     \
+        __attribute__((__section__(PER_CPU_BASE_SECTION section)))      \
         PER_CPU_ATTRIBUTES __typeof__(type) per_cpu__##name
-#else
+
 #define DEFINE_PER_CPU(type, name)                                      \
-        PER_CPU_ATTRIBUTES __typeof__(type) per_cpu__##name
+        DEFINE_PER_CPU_SECTION(type, name, "")
 
-#define DEFINE_PER_CPU_SHARED_ALIGNED(type, name)                     \
-        DEFINE_PER_CPU(type, name)
+#define DEFINE_PER_CPU_SHARED_ALIGNED(type, name)                       \
+        DEFINE_PER_CPU_SECTION(type, name, PER_CPU_SHARED_ALIGNED_SECTION) \
+        ____cacheline_aligned_in_smp
 
-#define DEFINE_PER_CPU_PAGE_ALIGNED(type, name)               \
-        DEFINE_PER_CPU(type, name)
-#endif
+#define DEFINE_PER_CPU_PAGE_ALIGNED(type, name)                         \
+        DEFINE_PER_CPU_SECTION(type, name, ".page_aligned")
+
+#define DEFINE_PER_CPU_FIRST(type, name)                                \
+        DEFINE_PER_CPU_SECTION(type, name, PER_CPU_FIRST_SECTION)
 
 #define EXPORT_PER_CPU_SYMBOL(var) EXPORT_SYMBOL(per_cpu__##var)
 #define EXPORT_PER_CPU_SYMBOL_GPL(var) EXPORT_SYMBOL_GPL(per_cpu__##var)